1. Field
The present invention relates to the field of kneeling push-pull exercise apparatus. More particularly, the present invention relates to a compact mobile exercise machine that exercises the abdominal, back and arm muscles in the kneel-prone-kneel movement.
2. State of the Art
The benefits of regular exercise to improve overall health, appearance and longevity are well documented in the literature. One of the most difficult muscle groups to exercise is the abdominals. For exercise enthusiasts the search continues for safe apparatus that provides exercise to tone the abdominals without back strain.
Many devices have appeared recently to aid the user in the performance of situps from a prone face-up position with the intent of easing back strain. Situps, even with assistive devices, have low appeal and often the devices find their way to a permanent storage area.
Another abdominal exercise method developed by the Royal Canadian Air Force requires a person to start in a kneeling position on hands and knees, then push his body forward, sliding out along his hands until prone with arms extended. The exerciser then returns to the kneeling position by reversing the sliding action. This is a most difficult exercise and would not be embraced by the average exercise participant. However, with an assistive apparatus the kneeling to nearly prone to kneeling sequence can be most beneficial to exercise the abdominal, back and arm muscles.
Various roller and track devices have attempted to provide assistive kneel-prone-kneel exercise. Tolchin in U.S. Pat. No. 1,984,165 provides a track and hand trolley with a compression spring biased to return the hands to the kneeling position similar to the Torso Track marketed by Fitness Quest on TV. Mattox in U.S. Pat. No. 5,499,961 offers a roller/track device having elastic cords attached to a hand grip roller where the elastic cord is also attached near the knee to return the hand grip roller towards the knees.
Osbourne in U.S. Pat. No. 3,797,824 shows a number of tracks which allow push-pull exercise. Oswald in U.S. Pat. No. 5,518,483 shows a push-pull type exercise device for the kneel-prone-kneel sequence having separate trolleys for the knees and hands that can be fixed or sliding. Palacios in U.S. Pat. No. 5,921,901 adds an elbow rest trolley to the trolley/track kneel-prone-kneel method. Wang in U.S. Pat. No. 5,295,935 shows a stretching device that provides a pair of poles that slide on tracks connected by elastic bands. Agamian in U.S. Pat. Nos. 3,572,701 and 3,589,720 shows a trolley/track for gymnastic exercise with the feet. Cencig in U.S. Pat. No. 3,101,944 offers trolley/track exercise.
The simplest kneel-prone-kneel device is the classic exercise wheel. Shiek et al. in U.S. Pat. No. D306,886 shows a pair of wheels rollably attached to a straight rod used for hand grip. Novak in U.S. Pat. No. 1,824,920 uses a pair of inline wheels with brake. Wilkin in U.S. Pat. No. 4,136,867 offers an exercise wheel with roller teeth to vibrate the user during push-pull operation. Mattox in U.S. Pat. No. 5,261,866 adds elastic tubing to the handles where the knees hold the tubing while the operator is in the push mode to assist in the return mode. A spiral spring is added to the exercise wheel in R.O.C. Pat. 276503 and to a pair of wheels by Barbeau in U.S. Pat. No. 2,821,394.
Ott in U.S. Pat. No. 3,752,475 shows a single wheel having a handle concentric with the wheel pivot axis several methods of windup for assistive return including a spiral spring within the wheel, elastic resilient elements acting in one plane within the wheel and a torsion bar/spring or stranded cable within the handle. Chiou in U.S. Pat. No. 5,707,325 adds a pair of spiral springs intended to engage the handle at different positions of wheel movement for non-linear torque windup about the handle as an assisted exercise wheel.
Waldeck in U.S. Pat. No. 3,707,284 shows an exercise tractor with multiple wheels in contact with the floor attached to a seat with elastic bands intended for seated leg exercise.
The assisted trolley/track apparatus lack compactness and tend to be costly to fabricate. The assisted exercise wheel tends to strain the wrist as the hand must resist the windup torque and tend to have only one direction of movement. None of the prior art provides a compact self-contained apparatus that stores energy during the push mode and returns the handle to the kneeling position without wrist strain.